Pfizer says antiviral effective against omicron

Lab studies show Pfizer’s COVID-19 treatment pill Paxlovid to be effective against the omicron variant, the company announced Tuesday.

Pfizer said three separate lab studies showed nirmatrelvir, the drug’s main protease inhibitor, maintains its effectiveness against omicron. A protease inhibitor is a class of drugs that stop a virus from replicating.

Pfizer announced the findings in a press release and said it was submitting them to pre-print medical journals.

The emergence of the omicron variant has led to questions about the effectiveness of Paxlovid, as well as other COVID-19 treatments, because the variant has many more mutations compared to earlier strains.

Paxlovid is seen as a major step forward in the fight against the virus, with trials showing that it reduced the risk of hospitalization or death by 89 percent in high-risk patients. Some experts have suggested that because the drug is a protease inhibitor, it won’t be as limited by mutations as other types of treatments.

The Food and Drug Administration last month authorized Paxlovid for use in high-risk patients. The fact that Paxlovid is a pill rather than an injection, as in previous treatments, is expected to make it more accessible and easier to take.